CD Calculator
↻ Updated 2026Enter your deposit, APY and term to see what a certificate of deposit is worth at maturity, the interest it earns, and how APY differs from the nominal APR.
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Runs entirely in your browser — nothing you enter is sent to us.How this works
How to read your CD maturity value
$10,000 at 4.75% APY for twelve months matures at $10,475.00 — and the reason it lands on exactly 4.75% of the deposit is worth understanding, because it's the entire point of the APY standard. Whatever the compounding frequency, a 4.75% APY held for one year pays 4.75%. That's what makes the number quotable.
How a CD's value at maturity is calculated from its APY
You'd think this runs forward from the rate. It runs backward from it. The tool takes the APY you entered, works out what nominal rate would produce that APY at your chosen compounding frequency, and only then compounds that nominal rate across the term.
The detour exists because APY and a compounding schedule are two descriptions of the same thing, and the bank quotes you the first. A 4.75% APY compounded daily comes from a 4.6409% nominal rate; compounded monthly, from 4.6496%. Different nominal rates, identical APY — which is precisely why Regulation DD makes banks quote the APY. It's the figure that's already done this arithmetic for you.
APR = c × ((1 + APY) ^ (1 ÷ c) − 1) ← back out the nominal rate value at maturity = deposit × (1 + APR ÷ c) ^ (c × years) interest = value at maturity − deposit years = term in months ÷ 12
- APY
- The annual percentage yield the bank quotes — the effective yield with compounding already included — the only rate worth comparing between offers
- APR
- The equivalent nominal rate, derived not entered — always lower than the APY, and lower the more often it compounds; shown in the details panel
- c
- Compounding periods per year — 365 daily, 12 monthly — changes the APR, but cannot change the maturity value; see the second example
- deposit
- What you lock in at the start — no further deposits — a CD takes one payment and closes
- years
- The term, converted from months — the slider runs 1 to 60 months in single-month steps
Because the APY→APR conversion and the compounding that follows are exact inverses, the two steps cancel. The whole calculation collapses to deposit × (1 + APY) ^ years, and the compounding selector becomes cosmetic — it moves the displayed APR and nothing else. This is correct, and it's the strongest possible demonstration of why APY is the number to shop on: once two banks quote you the same APY, their compounding schedules are no longer your problem.
One thing the model doesn't do is compound your interest into a second CD. The projection is a single CD held once, to maturity. What actually happens at maturity — most banks roll the balance into a new CD at the then-current rate unless you tell them otherwise, typically inside a grace period of a week or two — is a decision the calculator doesn't model, and a rollover at an unknown future rate is exactly the risk a fixed rate was protecting you from.
Worked examples
Example: $10,000 at 4.75% APY for 12 months
The calculator's defaults, with daily compounding selected. A one-year CD is the most common term, and one year is where APY is easiest to read: the interest is simply the APY times the deposit.
| Depositlocked for the full term | $10,000.00 |
| APYwhat the bank quotes | 4.75% |
| Equivalent APRthe nominal rate that compounds daily to 4.75% | 4.6409% |
| Value at maturityafter 365 daily compounding steps | $10,475.00 |
| Interest earnedexactly 4.75% of $10,000 | $475.00 |
$475.00 — 4.75% of the deposit, to the cent. Over exactly one year an APY does what it says on the tin, which is the whole reason the disclosure is written in APY rather than in a nominal rate plus a compounding schedule. The 4.6409% APR is the same deal described in the language banks used before Truth in Savings made them stop.
Example: the compounding selector, and the term slider, at the same APY
Two experiments on the defaults. First flip daily to monthly and watch nothing happen. Then leave compounding alone and drag the term. Only one of these sliders is doing anything to your money.
| 12 months, dailyAPR shown as 4.6409% | $10,475.00 |
| 12 months, monthlyAPR shown as 4.6496% — identical maturity value | $10,475.00 |
| 6 months$234.74 of interest | $10,234.74 |
| 24 months$972.56 — more than double the 12-month figure | $10,972.56 |
| 36 months$1,493.76 | $11,493.76 |
| 60 months$2,611.60 — the slider's maximum term | $12,611.60 |
The compounding choice is worth exactly nothing: $10,475.00 either way, and the same at every term we checked. The term is worth $2,136.60 — the difference between the 12-month and 60-month results at an unchanged 4.75%. Note also that 24 months earns $972.56 rather than twice $475.00, because the second year's interest is earned on $10,475 rather than on $10,000. That $22.56 is compounding, and it's the only part of a CD that isn't simple arithmetic.
Frequently asked questions
What happens if you withdraw from a CD early?
You pay a penalty set by the bank in the account agreement, assessed in months of interest rather than as a percentage of the balance — commonly around three months' interest on shorter terms and six to twelve on longer ones. There's no federal cap; the terms are whatever you agreed to when you opened it.
The detail that surprises people: if you haven't earned enough interest to cover the penalty, the difference comes out of your principal. Break a 12-month CD in month two and you can genuinely withdraw less than you deposited. The Truth in Savings Act requires the penalty to be disclosed before you open the account, so it's findable in advance — and it's the number to find, because it's the price of the liquidity you gave up. One consolation: an early-withdrawal penalty is deductible as an adjustment to income even if you don't itemise, and it appears in Box 2 of your 1099-INT.
Do you pay taxes on CD interest?
Yes, and — this is the part that catches people — usually before you can spend it. Under IRS Topic 403, interest is taxable in the year it's credited to your account, not the year the CD matures. A multi-year CD that pays nothing out until maturity still generates taxable interest every year along the way, reported on a 1099-INT, with the tax due from money that's still locked up.
It's ordinary income at your marginal rate, not capital gains. On the 60-month example above, $2,611.60 of interest at a 22% marginal rate costs about $575 in federal tax, spread across five returns rather than landing on one. The maturity figures on this page are all pre-tax. CDs held inside an IRA work differently — the interest isn't taxed as it's credited — which is why CDs turn up inside retirement accounts more often than their headline rate would suggest.
What is the difference between APY and interest rate on a CD?
The interest rate is the rate before compounding; the APY is the yield after it. This calculator shows both for the same CD: enter 4.75% APY with daily compounding and it reports an equivalent APR of 4.6409%. Same CD, same $475.00, two ways of saying it.
The APY is always the higher of the two, and the gap grows the more frequently interest compounds — which is why quoting the nominal rate would let a bank look competitive while paying less, and why Regulation DD requires deposit accounts to be advertised in APY. It forces every bank to state the number after the arithmetic instead of before it. If an offer quotes a "rate" rather than an APY, it isn't comparable to anything until you convert it.
What is a CD ladder and how does it work?
Splitting one deposit across several CDs with staggered maturities instead of putting it all in one. Rather than $10,000 in a single 5-year CD, you'd put $2,000 into each of a 1-, 2-, 3-, 4- and 5-year CD. As each matures you roll it into a new 5-year CD, so once the ladder is built you have one maturing every year while the rest earn the longer-term rate.
What it buys is a hedge against being wrong about rates. Lock everything into a 5-year CD and you lose if rates rise; keep everything short and you lose if they fall. A ladder guarantees you'll never have all of it at the best rate and never all of it at the worst — a defensible trade when nobody can time the next move. Model each rung here separately: this page prices one CD at a time, and a ladder is just several of those.
Are CDs worth it compared to high-yield savings?
The trade is certainty against access. A CD fixes your rate for the term and charges you months of interest to leave; a high-yield savings account can be emptied on a Tuesday, and its rate cut on the Wednesday. Which pays more over a given year is a bet on rates that neither you nor the bank can settle in advance.
The CD wins when rates fall — you keep a yield the market no longer offers — and loses when they rise, with your money committed at the old number while new offers pass it. The published guidance tends not to pick a winner and instead maps the products onto the money: the CFPB's savings guidance points to penalty-free accounts for money that might be needed, while CDs are conventionally described as fitting money with a known date attached. Compare the same deposit in the high-yield savings calculator and the money market calculator.
What this CD calculator leaves out
One deposit, one rate, held to maturity. That's a good description of a CD and an incomplete description of owning one.
- No early-withdrawal penalty — The single largest omission. Every figure assumes you hold to maturity; there's no input for the penalty and no way to model breaking the CD. Since penalties run to several months of interest and can eat into principal on a young CD, the real downside case isn't on this page at all.
- Nothing happens at maturity — The projection stops at the term. Real CDs usually auto-renew at the prevailing rate unless you act within a short grace period, and that rollover rate is unknowable today — so a 12-month CD is a 12-month decision that quietly becomes a new one, at a rate nobody has quoted yet.
- Tax is absent, and its timing is the point — All figures are pre-tax. Interest is ordinary income taxed as it's credited rather than at maturity, which means a multi-year CD produces a tax bill each year from money you can't reach without a penalty. That timing mismatch has no representation here.
- Interest is assumed to stay in the CD — The model compounds every dollar of interest back into the balance. Some CDs pay interest out monthly or quarterly to a linked account instead, which is a materially different product: your money doesn't compound, and the maturity value is just the deposit back.
- The compounding selector doesn't change the money — Worth stating plainly, because the UI suggests otherwise. Choosing daily or monthly moves only the displayed equivalent APR — the maturity value is identical to the cent at every term. That's a true fact about APY rather than an error, but if you came to the page expecting daily compounding to pay more than monthly at the same APY, the answer is that it can't.
- No inflation adjustment — $12,611.60 after five years is in future dollars. At 3% inflation it buys roughly what $10,878 buys today — a real gain of about $878 on $10,000, against the $2,611.60 the headline reports. A fixed rate protects you from rate cuts, not from prices.
- ·Standard compound-interest / APY formulas
- ·FDIC / NCUA deposit insurance — Insured up to $250,000 per depositor, per institution
Rates, brackets and limits here are checked against primary sources. If a number still looks off, email support@realmoneyiq.com and we'll review and fix it.
RealMoneyIQ provides free educational calculators, not financial, tax, investment or legal advice. Results are estimates based on the assumptions you enter and publicly published rates; your actual outcome will differ. Always confirm decisions with a licensed professional who knows your full situation.